The Middle Department was an administrative military district created by the United States War Department

United States Department of War

The United States Department of War, also called the War Department , was the United States Cabinet department originally responsible for the operation and maintenance of the United States Army...

 early in the American Civil War

American Civil War

The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

 to administer the troops in the Middle Atlantic states

Mid-Atlantic States

The Mid-Atlantic states, also called middle Atlantic states or simply the mid Atlantic, form a region of the United States generally located between New England and the South...

.

The department was created on March 22, 1862 by the Adjutant General

Adjutant general

An Adjutant General is a military chief administrative officer.-Imperial Russia:In Imperial Russia, the General-Adjutant was a Court officer, who was usually an army general. He served as a personal aide to the Tsar and hence was a member of the H. I. M. Retinue...

's Office in Washington, D.C.

Washington, D.C.

Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....

. It combined all Federal troops in the states of New Jersey

New Jersey

New Jersey is a state in the Northeastern and Middle Atlantic regions of the United States. , its population was 8,791,894. It is bordered on the north and east by the state of New York, on the southeast and south by the Atlantic Ocean, on the west by Pennsylvania and on the southwest by Delaware...

, Delaware

Delaware

Delaware is a U.S. state located on the Atlantic Coast in the Mid-Atlantic region of the United States. It is bordered to the south and west by Maryland, and to the north by Pennsylvania...

, Pennsylvania

Pennsylvania

The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...

 and the counties of Anne Arundel

Anne Arundel County, Maryland

Anne Arundel County is a county located in the U.S. state of Maryland. It is named for Anne Arundell , a member of the ancient family of Arundells in Cornwall, England and the wife of Cæcilius Calvert, 2nd Baron Baltimore. Its county seat is Annapolis, which is also the capital of the state...

, Baltimore

Baltimore County, Maryland

Baltimore County is a county located in the northern part of the US state of Maryland. In 2010, its population was 805,029. It is part of the Baltimore-Washington Metropolitan Area. Its county seat is Towson. The name of the county was derived from the barony of the Proprietor of the Maryland...

, Cecil

Cecil County, Maryland

Cecil County is a county located in the U.S. state of Maryland. It is part of the Delaware Valley. It was named for Cæcilius Calvert, 2nd Baron Baltimore , who was the first Proprietary Governor of the colony of Maryland from 1632 until his death in 1675. The county seat is Elkton. The newspaper...

, and Harford

Harford County, Maryland

Harford County is a county in the U.S. state of Maryland. In 2010, its population was 244,826. Its county seat is Bel Air. Harford County forms part of the Baltimore-Washington Metropolitan Area.-History:...

 in Maryland

Maryland

Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...

, with headquarters in Baltimore, Maryland. Maj. Gen.

Major general (United States)

In the United States Army, United States Marine Corps, and United States Air Force, major general is a two-star general-officer rank, with the pay grade of O-8. Major general ranks above brigadier general and below lieutenant general...

 John A. Dix

John Adams Dix

John Adams Dix was an American politician from New York. He served as Secretary of the Treasury, U.S. Senator, and the 24th Governor of New York. He was also a Union major general during the Civil War.-Early life and career:...

 was designated as its first commander.

The Middle Department was dissolved July 22 1862, when it was renamed VIII Corps. Although no longer an official organization, the Middle Department designation continued to be used in reference to VIII Corps and the general administrative district that it originally encompassed.

Commanders

• Major General John A. Dix - March 22, 1862 to June 9, 1862
• Major General John E. Wool
  John E. Wool
  John Ellis Wool was an officer in the United States Army during three consecutive U.S. wars: the War of 1812, the Mexican-American War and the American Civil War. By the time of the Mexican-American War, he was widely considered one of the most capable officers in the army and a superb organizer...
  
  - June 9, 1862 to July 22, 1862